QS Study

The uterus is a secondary sex organ. It is an organ of the female reproductive system. Secondary sex organs are components of the reproductive tract that mature during puberty under the influence of sex hormones produced from primary sex organs.

Histological structure of the uterus

The wall of the uterus shows the following structures from inward to outward –

(A) Endometrium: inner mucous membrane lining the uterus

It consists of the living epithelium and lamina propria containing simple tubular glands. It is as follows – Columnar epithelium up to the supravaginal part of the cervix, stratified squamous epithelium in vaginal part.

The endometrium is subdivided into the following three zones during the secretory phase of the menstrual cycle. Inward to outward –

  1. Stratum compactum.
  2. Stratum spongiosum.
  3. Stratum basale.

(B) Myometrium: thick smooth muscle layer. Cells of this layer undergo hypertrophy and hyperplasia during pregnancy in preparation to expel the fetus at birth.

The muscular wall consists of –

  • An inner longitudinal muscle layer.
  • A middle circular layer.
  • An outer longitudinal layer.

(C) Perimetrium. a double-layered membrane, continuous with the abdominal peritoneum.

It is the scrosal layer consisting of a single layer of mesothelial all.

Fig: Histological Structure of Uterus

Development

Fundus and body: Develop by the fusion of the intermediate horizontal parts of two paramesonephric ducts.

Cervix: Develops by the fusion of lower vertical parts of two paramesonephric duct.

Artery supply of uterus –

The uterus is supplied –

(i) Chiefly by the two uterine arteries,

(ii) Partly by the ovarian arteries.